Methods for creating foam-like texture

ABSTRACT

Methods for creating a foam-like texture on an implantable material are provided. More particularly, methods for creating foam-like texture on implantable silicone materials are provided.

RELATED APPLICATION

This application claims priority to U.S. Provisional Patent ApplicationNo. 61/414,250, filed Nov. 16, 2010, the entire disclosure of which isincorporated here by reference.

FIELD OF THE INVENTION

The present invention pertains to methods for creating a foam-liketexture on an implantable material. More particularly, the presentinvention relates to methods for creating foam-like texture onimplantable silicone materials.

BACKGROUND

Prostheses or implants for augmentation and/or reconstruction of thehuman body are well known. Capsular contracture is a complicationassociated with surgical implantation of prostheses, particularly withsoft implants, and even more particularly, though certainly notexclusively, with fluid-filled breast implants.

Capsular contracture is believed to be a result of the immune systemresponse to the presence of a foreign material in the body. A normalresponse of the body to the presence of a newly implanted object, forexample a breast implant, is to form a capsule of tissue, primarilycollagen fibers, around the implant. Capsular contracture occurs whenthe capsule begins to contract and squeeze the implant. This contracturecan be discomforting or even extremely painful, and can cause distortionof the appearance of the augmented or reconstructed breast. The exactcause of contracture is not known. However, some factors may includebacterial contamination of the implant prior to placement, submuscularversus subglandular placement, and smooth surface implants versustextured surface implants, and bleeding or trauma to the area.

Surface texturing has been shown to reduce capsular contracture whencompared to what are known as “smooth” surface implants.

There is still a need for a more optimal surface textured implant thatfurther reduces the potential for capsular contracture. The presentinvention addresses this need.

SUMMARY OF INVENTION

The present invention pertains to methods for creating a foam-liketexture on a material that is suitable for implantation in a mammal.

In one aspect, the present invention provides a method of making amaterial having a foam-like texture and suitable for implantation in amammal, the method comprising:

-   -   1) applying a texturing material lacking a foam-like texture        onto a mandrel of a desired shape;    -   2) placing a foam-like material over the texturing material;    -   3) applying pressure to integrate the foam-like material and the        texturing material;    -   4) allowing the foam-like texture to set in the texturing        material;    -   5) removing the foam-like material from the texturing material        which has acquired a foam-like texture.

Metal rings may be used to clamp and immobilize the foam-like materialas the foam-like material is pressed down on and integrated into thenon-solid texturing material; the weight of the metal rings can aid inpressing the foam-like material and the texturing material together. Inanother variant, a base coat, which may be the same material as thetexturing material, may be spread onto the mandrel and solidified beforethe texturing material is spread onto the base coat.

In another aspect, the present invention provides a method of making amaterial having a foam-like texture and suitable for implantation in amammal, the method comprising:

-   -   1) applying a texturing material lacking a foam-like texture        onto a film coater;    -   2) placing a foam-like material over the texturing material;    -   3) applying pressure to integrate the foam-like material and the        texturing material;    -   4) allowing the foam-like texture to set in the texturing        material;    -   5) removing the foam-like material from the texturing material        which has acquired a foam-like texture.

A base coat, which may be the same material as the texturing material,may be spread onto the film coater and solidified before the texturingmaterial is spread onto the base coat.

In another aspect, the present invention provides a method of making amaterial having a foam-like texture and suitable for implantation in amammal, the method comprising:

-   -   1) applying pressure to integrate a first texturing material        lacking a foam-like texture and a foam-like material;    -   2) allowing the foam-like texture to set in the first texturing        material;    -   3) applying pressure to integrate a second texturing material        with the composite of the first texturing material and the        foam-like material;    -   4) allowing the foam-like texture to set in the second texturing        material;    -   5) removing the foam-like material from the texturing materials        which have acquired a foam-like texture.

The present invention also provides a method for creating one or morefoam-like-textured surfaces on a breast prosthesis or implant. Atextured material, having the desired dimensions, that acquires afoam-like texture through any of the novel methods described above, canbe bonded, by a suitable, biocompatible adhesive, to a smooth shellbreast prosthesis, to produce a breast prosthesis having afoam-like-textured surface.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention may be more clearly understood and certain aspectsand advantages thereof better appreciated with reference to thefollowing Detailed Description when considered with the accompanyingDrawings of which:

FIG. 1 is a front perspective view and partial cross-section view whichreflects an embodiment of the current invention in which a silicone basematerial is first spread onto a mandrel and cured, then the mandrel isdipped in a silicone texturing material; a piece of polyurethane foamclamped down by metal rings is placed over and pressed down against thesilicone texturing material before the silicone texturing material iscured and acquires the texture of the polyurethane foam.

FIG. 2 is an illustration of an embodiment of the current invention inwhich a base material, which can be a silicone material, is the firstlayer of material cast onto the Teflon surface of a film coater; thetexturing material, which can be a silicone material, is the secondlayer of material placed on top of the base material and a piece ofpolyurethane foam is the uppermost material.

FIGS. 3A & 3B are SEM micrographs of the top view of a siliconematerial, MED-4815, which has acquired a foam-like texture through the“sheet approach.”

FIGS. 4A & 4B are SEM micrographs of the cross-sectional view of asilicone material, MED-6400, which has acquired a foam-like texturethrough the “sheet approach.”

FIG. 5 is an illustration of open and closed cell foam structures.

FIGS. 6A & 6B are SEM micrographs showing the foam-like texture of asilicone material, MED-2000, that acquired its foam-like texture frompolyurethane foam under the high pressure of 100 psi. 6A is across-sectional view and 6B is a top view.

FIGS. 7A & 7B are SEM micrographs showing the foam-like texture of asilicone material, MED-2000, that acquired its foam-like texture frompolyurethane foam under the low pressure of 10 psi. 7A is across-sectional view and 7B is a top view.

DETAILED DESCRIPTION

The present invention pertains to methods for creating a foam-liketexture on an implantable material. More particularly, the presentinvention relates to methods for creating foam-like texture onimplantable silicone materials. Even more specifically, the presentinvention relates to methods for creating polyurethane-foam-like textureon implantable silicone materials.

The present invention also relates to methods for creating one or morefoam-like texture surfaces on breast prostheses or implants.

As used herein, “foam-like texture” refers to texture that ischaracterized by interconnected pores or the like, or texture thatresembles or approximates such a texture.

As used herein, “texturing material” refers to a substantiallynon-biodegradable polymeric material that acquires a foam-like texturethrough the novel methods disclosed herein. In the “EXAMPLES” section,silicone is the texturing material. Other examples of texturing materialinclude, but are not limited to: polyurethane, polyesters, polyolefins,polyisobutylene, ethylene-alphaolefin copolymers, acrylic polymers andcopolymers, ethylene-co-vinylacetate, polybutylmethacrylate, vinylhalide polymers and copolymers (e.g., polyvinyl chloride), polyvinylethers (e.g., polyvinyl methyl ether), polyvinylidene halides (e.g.,polyvinylidene fluoride and polyvinylidene chloride), polyacrylonitrile,polyvinyl ketones, polyvinyl aromatics (e.g., polystyrene), polyvinylesters (e.g., polyvinyl acetate), copolymers of vinyl monomers with eachother and olefins (e.g., ethylene-methyl methacrylate copolymers,acrylonitrile-styrene copolymers, ABS resins, and ethylene-vinyl acetatecopolymers), polyamides (e.g., Nylon 66 and polycaprolactam), alkydresins, polycarbonates, polyoxymethylenes, polyimides, polyethers, epoxyresins, rayon, ryon-triacetate, cellulose, cellulose acetate, cellulosebutyrate, cellulose acetate butyrate, cellophane, cellulose nitrate,cellulose propionate, cellulose ethers, carboxymethyl cellulose, andcombinations thereof. The texturing material used for the novel methodsdisclosed herein can be selected or enhanced based upon considerationssuch as resistance to acids and bases, mechanical strength, resistanceto radiation, such as UV, exposure, and resistance to metal salts orsolvents. As used herein, a “base coat” can be of any material that the“texturing material” can be.

As used herein, “foam-like material” refers to a material that has a“foam-like texture” and is used to impart a foam-like texture to a“texturing material” through the novel methods disclosed herein. In the“EXAMPLES” section, polyurethane foam is the foam-like material. Thefollowing are other non-limiting examples of foam-like material ormaterial which can be used to make foam-like material: polyethylene,polyethylene vinyl acetate, polystyrene, polyvinyl alcohol, Styrofoam,polyolefin, polyester, polyether, polysaccharide, polyamide,polyacrylate; a material which contains aromatic or aliphatic structuresin the backbone, as functionalities, cross-linkers or pendant groups, ora copolymer, terpolymer, or quarternaly polymer thereof; metal, metalfoam, ceramic, ceramic foam, and combinations thereof.

Novel methods disclosed herein generally comprise:

-   -   1) integrating a texturing material lacking a foam-like texture        with a foam-like material by pressing them together;    -   2) removing the foam-like material from the solidified texturing        material which has acquired a foam-like texture.

If the texturing material is a non-solid prior to integration with afoam-like material, the texturing material would be solidified followingintegration.

In one aspect, the present invention provides a method of making amaterial having a foam-like texture and suitable for implantation in amammal, the method comprising:

-   -   1) applying a texturing material lacking a foam-like texture        onto a mandrel of a desired shape;    -   2) placing a foam-like material over the texturing material;    -   3) applying pressure to integrate the foam-like material and the        texturing material;    -   4) allowing the foam-like texture to set in the texturing        material;    -   5) removing the foam-like material from the texturing material        which has acquired a foam-like texture.

The above aspect of the present invention is illustrated in examples 1and 2 in the “EXAMPLES” section. Metal rings may be used to clamp andimmobilize the foam-like material as the foam-like material is presseddown on and integrated into the non-solid texturing material; the weightof the metal rings can aid in pressing the foam-like material and thetexturing material together. A base coat, which may be the same materialas the texturing material, may be spread onto the mandrel and solidifiedbefore the texturing material is spread onto the base coat. The step ofallowing the foam-like texture to set in the texturing material maycomprise solidifying the texturing material, such as by heat-curing.

In another aspect, the present invention provides a method of making amaterial having a foam-like texture and suitable for implantation in amammal, the method comprising:

-   -   1) applying a texturing material lacking a foam-like texture        onto a film coater;    -   2) placing a foam-like material over the texturing material;    -   3) applying pressure to integrate the foam-like material and the        texturing material;    -   4) allowing the foam-like texture to set in the texturing        material;    -   5) removing the foam-like material from the texturing material        which has acquired a foam-like texture.

The step of allowing the foam-like texture to set in the texturingmaterial may comprise

solidifying the texturing material, such as by heat-curing. A base coat,which may be the same material as the texturing material, may be spreadonto the film coater and solidified before the texturing material isspread onto the base coat. This embodiment is illustrated in example 3in the “EXAMPLES” section.

In another aspect, the present invention provides a method of making amaterial having a foam-like texture and suitable for implantation in amammal, the method comprising:

-   -   1) applying pressure to integrate a first texturing material        lacking a foam-like texture and a foam-like material;    -   2) allowing the foam-like texture to set in the first texturing        material;    -   3) applying pressure to integrate a second texturing material        with the composite of the first texturing material and the        foam-like material;    -   4) allowing the foam-like texture to set in the second texturing        material;    -   5) removing the foam-like material from the texturing materials        which have acquired a foam-like texture.

This embodiment is illustrated in examples 4 and 5 in the “EXAMPLES”section.

EXAMPLES

Types of silicones mentioned in the following examples were obtainedfrom NuSil Silicone Technology, Carpinteria, Calif.

Example 1

Uncured Room-Temperature-Vulcanizing (“RTV”) silicone, for example,MED-1511, is spread onto a mandrel of a desired shape as a layer havinga thickness of 200 μm. A polyurethane foam is placed over the RTVsilicone and the mandrel with the aid of metal rings which clamp thefoam in place. The weight of the metal rings asserts a force ofapproximately 30 psi against the polyurethane foam, the RTV silicone andthe mandrel. After the RTV silicone is cured, the metal ring and mandrelare removed from the composite of the cured RTV silicone andpolyurethane foam. The composite of the cured RTV silicone andpolyurethane foam is submerged in hydrochloric acid for five minutes toremove the polyurethane foam. Excess hydrochloric acid is removed bywashing in distilled water for two minutes. The resulting product is asilicone material having a foam-like texture.

Example 2

A base coat of uncured High-Temperature-Vulcanizing (“HTV”) siliconedispersed in xylene, for example, MED-6400 dispersed in xylene, isspread onto a mandrel and cured (in FIG. 1, the “silicone basematerial”). The mandrel covered by a base coat is then dipped in asecond uncured HTV silicone dispersed in xylene (in FIG. 1, the“silicone texturing material”), for example, MED 6640 in xylene, untilthe second coat of HTV silicone dispersed in xylene reaches a thicknessof (about) 250 μm. Then the xylene is removed from the HTV siliconematerials by devolatilization in a fume hood. Next, a piece ofpolyurethane foam is placed over and pressed down against theHTV-silicone-coated mandrel. One way to apply the polyurethane foam tothe HTV-silicone-coated mandrel is to clamp the foam between metal rings(see FIG. 1), then place the exposed portion of the foam that iscircumscribed within the rings over the mandrel; the metal ringsimmobilize the foam to keep it in place and press the foam against theHTV-silicone-coated mandrel. With the polyurethane foam integrated intothe second coat of HTV silicone, the second coat of HTV silicone isheat-cured. After the silicone has been cured and acquired the textureof the polyurethane foam, the polyurethane foam is removed byapplication of acid or hot solvent.

Example 3 Silicone Sheet Approach

An uncured silicone material (1 mm thick, 5″×5″), such as MED-4815dispersed in xylene (50 ml, 30% w/w), is cast onto a Teflon sheet on thesurface of a film coater. After the film coater creates an even sheet ofthe silicone, the Teflon sheet is taken off of the film coater and thesilicone is cured in an oven at 126° C. for 2 hours. The Teflon sheetwith the cured, first layer is then placed back on the film coater.Then, an uncured, second layer of silicone material, which may be thesame material as the cured, first layer, is spread onto the surface ofthe cured, first layer. The film coater creates an even sheet of theuncured second layer of silicone. The Teflon sheet is then removed fromthe film coater and placed in a mechanical press. Next, polyurethanefoam is placed over the uncured, second layer of silicone material and,using the press set to 50 psi, the polyurethane foam is pressed into theuncured silicone for 1 minute, which results in a 70% integration. “%integration” as used herein refers to the percent of the thickness ofthe texturing material that the foam-like material is pressed into. Theuncured silicone is then cured at 126° C. for 1 hour and acquires thetexture of the polyurethane foam. The Teflon sheet is then peeled off ofthe cured silicone and discarded. The polyurethane foam is removed fromthe cured silicone by washing the polyurethane-silicone composite in 300ml of 38% concentrated HCl for 5 minutes, followed by a 3-minute wash indistilled water. FIG. 2 shows the layers of material on the Teflonsurface of the film coater: the “base material” is the first layer ofsilicone material; the “texturing material” is the second layer ofsilicone material which acquires the texture of the polyurethane foam.

Example 4

Using a press set to 60 psi, polystyrene-block-polyisoprene-blockpolystyrene (“polystyrene foam”) is pressed into an uncured, 1 mm-thicksheet of a silicone material, such as MED-4810. The silicone is thencured at 100° C. for 2 hours, generating a cured silicone-polystyrenefoam composite. A dilute second silicone material, which may be the sameas or different from the first, such as MED-4810 dispersed indichloromethane (10% w/w), is poured onto the cured silicone-foam; thecured silicone-foam coated with uncured silicone is immediately pressedfor 5 seconds under a pressure of 40 psi between two Teflon or aluminumsheets. Next, the uncured silicone coating the cured silicone-foam iscured at 100° C. for 1 hour. The polystyrene foam is removed from thesilicone by soaking the silicone in 200 ml of hexane overnight.

Example 5

First, a polyurethane sheet is completely submerged in a bath ofsilicone dispersed in xylene, for example, MED-4714 dispersed in xylene(10% w/w); the fully-submerged polyurethane sheet is pressed at 20 psito enable the silicone dispersion to fully enter and saturate thepolyurethane. The polyurethane sheet is then removed from the bath andexcess silicone dispersion is allowed to run off of it. Thesilicone-polyurethane composite is then cured at 120° C. for one hour.The cured silicone-polyurethane composite is then pressed, at a pressureof 40 psi, into an uncured, 2 mm-thick sheet of a second siliconematerial, for example, MED-4815. The uncured second silicone materialcoating the cured silicone-polyurethane composite is cured at 120° C.for one hour, resulting in silicone that has acquired the foam-liketexture of the polyurethane. The polyurethane is then removed from thesilicone materials by dipping the silicone-polyurethane composite inDMSO (at 130° C.) for 20 minutes.

In some embodiments, suction can be used as an aid in integrating thefoam-like material and the texturing material. Suction can be applied toa foam-like material to pull the texturing material, for example,silicone in solvent, through the foam-like material. The more integratedthe foam-like material and the texturing material, the thicker thefoam-like texture that is created in the texturing material. Suction canalso remove any excess texturing material, meaning texturing materialbeyond that which is sufficient to saturate the foam-like material, ortexturing material that has not smoothly integrated into the foam-likematerial, but is instead blocking the pores of the foam-like material.

In some embodiments, the foam-like texture created in a texturingmaterial, such as a silicone material, through the novel methodsdisclosed herein may be heterogeneous, as opposed to homogeneous. A“homogeneous” foam-like texture generally refers to a texture havingapproximately the same number of interconnections per pore (see Fig. forillustration of “interconnections”). A “heterogeneous” foam-like texturegenerally refers to a texture having variation in the number ofinterconnections per pore.

An example of a heterogeneous foam-like texture that can be created in atexturing material would be a texture comprising a gradient ofinterconnections between pores: there is an increase in the number ofinterconnections per pore from one surface of the texturing material tothe opposing surface (see FIG. 4A). In a cross section view, a texturingmaterial having acquired a foam-like texture with a gradient ofinterconnections would resemble a closed cell foam at one end, but anopen cell foam at the other end, with pores closer to the end resemblingan open cell foam each having more interconnections than pores closer tothe end resembling a closed cell foam (see FIG. 4A). A closed cell foamis generally characterized as having two or fewer interconnections perpore and an open cell foam as having three or more interconnections perpore (see FIG. 5).

For example, a heterogeneous foam-like texture can be created in atexturing material, such as silicone, if excess silicone, meaning moresilicone than is necessary to saturate the foam-like material, is used.Because the silicone is in excess, the bottom surface of the silicone,which is the surface opposite the top surface onto which the foam-likematerial was pressed, would be a layer of silicone containing few or nopores; however, there are more and more pores and more interconnectionsper pore closer to the surface of the silicone onto which the foam-likematerial was pressed.

Whether and to what degree a texturing material acquires a heterogeneousfoam-like texture can be due to many different factors, such as theamount of texturing material used relative to the foam-like material,the concentration of texturing material in solvent, the amount ofpressure used to press the foam-like material and texturing materialtogether, and changing the amount of solvent in which the texturingmaterial is dispersed when the foam-like material is pressed against thetexturing material.

The foam-like material used to impart a foam-like texture to a texturingmaterial may have about 1% to about 99% porosity. As used herein, “%porosity” refers to % of the total volume of the foam-like material thatcomprise void or empty space. Consequently, a texturing material thathas acquired a foam-like texture from a foam-like material may haveabout 1% to about 99% porosity.

The foam-like material may have a pore size of about 100-1000 μm(relative standard deviation (“RSD”) of about 0.01-100%); aninterconnection size of about 30-700 μm (RSD of 0.01-100%);interconnections per pore of about 2-20 (RSD of 0.01-50%); and anaverage pore to interconnection size ratio of about 3-99%.

In some embodiments, the foam-like material has a pore size of about300-700 μm (RSD of 1-40%); an interconnection size of about 100-300 μm(RSD of 1-40%); interconnection per pore of about 3-10 (RSD of 1-25%)and an average pore to interconnection size ratio of about 10-99%.

In an exemplary embodiment, the foam-like material comprises a material,for example, polyurethane or other suitable material, having a pore sizeof 472+/−61 μm (RSD=13%), interconnection size of 206+/−60 μm (RSD=29%),interconnection per pore of 9.6+/−1.8 (RSD=19%), and pore tointerconnection size ratio of 44%.

The texturing material can be solvent-free or dispersed in solvent whenapplied to a foam-like material for integration. One example of atexturing material that does not require dispersion in solvent isRoom-Temperature-Vulcanizing silicone. The concentration of texturingmaterial in solvent can range from about 5 to about 100% w/w. Thegreater the concentration of texturing material in solvent, the greaterthe density (mass per unit volume) of the end product, the texturingmaterial which has acquired a foam-like texture, such as a siliconematerial that has acquired a foam-like texture. Non-limiting examples ofuseful solvents include acetone, xylene, dichloromethane, chloroform,dimethyl sulfoxide, water, methanol, methyl acetate, hexane, benzenetoluene, and isopropyl alcohol.

The texturing material can be a solid, for example, an RTV silicone, orfluid material. Fluid materials include dispersions, solutions,emulsions, or a combination thereof. The viscosity of fluid texturingmaterials may range from approximately 10 to 3,000,000 cP.

Pressure applied to integrate a texturing material and foam-likematerial may range from 0.5 to 500 psi. In other embodiments, thepressure may range from 1 to 200 psi. Generally, the greater thepressure applied, the greater the degree of integration between thetexturing material and the foam-like material, and the greater theextent and thickness of the foam-like texture layer that is created inthe texturing material. Thus, the pressure can be varied depending onhow extensive of a foam-like texture is desired to be created in thetexturing material.

FIGS. 6A & 6B are SEM micrographs showing the foam-like texture of asilicone material, MED-2000, that acquired its foam-like texture frompolyurethane foam under the high pressure of 100 psi. 6A is across-sectional view and 6B is a top view.

FIGS. 7A & 7B are SEM micrographs showing the foam-like texture of asilicone material, MED-2000, that acquired its foam-like texture frompolyurethane foam under the low pressure of 10 psi. 7A is across-sectional view and 7B is a top view.

Because greater pressure was applied for the silicone texturing materialshown in FIG. 6 than that shown in FIG. 7, there is a greater degree ofintegration for the one in FIG. 6 (compare, for example, the crosssectional images in 6A with that in 7A; the foam-like texture layer thatis created is thicker in 6A than in 7A).

Also, the morphology of the foam-like material may change if too great apressure is exerted to integrate the foam-like material and thetexturing material, which would affect the foam-like texture that iscreated in the texturing material as well. What counts as too great apressure depends on foam-like and texturing materials used; a set offoam-like and texturing materials pressed together under a certainpressure would result in the texturing material acquiring foam-likecharacteristics that differ from those it would acquire if pressed at ahigher pressure.

If the texturing material used is dispersed in solvent, the type ofsolvent can affect the time it takes to integrate the texturing materialand the foam-like material. For example, it generally takes less time tointegrate a RTV silicone dispersed in dichloromethane with a foam-likematerial than a HTV silicone dispersed in xylene with a foam-likematerial.

Also, the foam-like material may swell when contacted with the solventin which the texturing material is dispersed, and this can alter thetexture of the foam-like material and hence the foam-like texture thatthe foam-like material imparts to the texturing material.

The process for removing the foam-like material after the foam-likematerial has imparted a foam-like texture to the texturing materialvaries depending on the foam-like material used. Any means known tothose of skill the art and suitable for removing the foam-like materialwithout substantially affecting the texturing material that has acquireda foam-like texture may be used. Agents used for removal may be a base,a solvent, an enzyme, an acid, heat, oxidation, uv light, gammairradiation, visible light, infrared light or a combination thereof.When the foam-like material used is polyurethane, the polyurethane maybe removed by, for example, dimethyl sulfoxide, hydrogen peroxide,hydrochloric acid, dimethyl formamide, acetone, or a combinationthereof. The removing process may not remove all of the foam-likematerial all at once, so it may be repeated as desired.

The present invention also provides a method for creating one or morefoam-like-textured surfaces on a breast prosthesis or implant. Atextured material, having the desired dimensions, that acquires afoam-like texture through any of the novel methods described above, canbe bonded, by a suitable, biocompatible adhesive, to a smooth shellbreast prosthesis, to produce a breast prosthesis having afoam-like-textured surface.

In some embodiments, the methods disclosed hereinbefore may be used tocreate a foam-like texture on material that has already been texturedthrough other means. For example, a texturing material, such as asilicone material, may undergo a texturing process as described in U.S.Pat. No. 5,007,929 (“Quaid patent”), which is incorporated by referenceherein, before it undergoes any of the methods disclosed hereinbefore toacquire a foam-like texture.

In some embodiments, a breast implant may have a very thin, for example,0.5 mm-thick, texturing material having a foam-like texture bonded toits front surface and a thicker, for example, 3 mm-thick, texturingmaterial having a foam-like texture bonded to its back surface.Generally, the thickness of the texturing material having a foam-liketexture used for bonding to surface(s) of breast implants can varybetween approximately 0.1 to 50 mm. The foam-like material used tocreate texturing materials having a foam-like texture for bonding tosurface(s) of breast implants can vary between approximately 0.1 to 250mm thick.

What is claimed is:
 1. A method of making a textured breast implant, themethod comprising: applying a texturing material onto a mandrel havingthe shape of a breast implant; placing a polyurethane foam sheet ontothe texturing material; causing integration between the texturingmaterial and the polyurethane foam sheet by pressing the polyurethanefoam sheet into the texturing material; generating a composite of curedtexturing material and polyurethane foam by curing the texturingmaterial after the step of causing integration; and after the step ofgenerating the composite by curing, removing the polyurethane foam fromthe cured texturing material by application of a solvent of polyurethaneto the composite, to thereby obtain a material having the shape of abreast implant and a surface texture characterized by interconnectedpores.
 2. The method of claim 1, further comprising using clamps tostabilize the polyurethane foam sheet as it is placed onto andintegrated with the texturing material.
 3. The method of claim 1,wherein the texturing material is a silicone material.
 4. A method ofproducing a textured surface on an implantable breast prosthesis, themethod comprising: applying a base coat to a breast implant mandrel;applying to the base coat, a texturing material comprising an uncuredsilicone dispersion; placing a polyurethane foam sheet onto thetexturing material; applying pressure to integrate the polyurethane foamand the texturing material; curing the texturing material with thepolyurethane foam integrated thereto; after the step of curing, removingthe polyurethane foam from the cured texturing material by applicationof a solvent capable of dissolving polyurethane, to thereby obtain amaterial having the shape of a breast implant and a surface texturecharacterized by interconnected pores.
 5. The method of claim 4, whereinthe thickness of the polyurethane foam sheet is between about 0.1 mm toabout 250 mm and the thickness of the texturing material is betweenabout 0.1 mm to about 50 mm.
 6. The method of claim 1 wherein thesolvent is hydrochloric acid.
 7. The method of claim 1 wherein thesolvent is hexane.
 8. The method of claim 1 wherein the solvent isdimethyl sulfoxide (DMSO).
 9. The method of claim 4 wherein the solventis hydrochloric acid.
 10. The method of claim 4 wherein the solvent ishexane.
 11. The method of claim 4 wherein the solvent is dimethylsulfoxide (DMSO).